Dividing Wall Column GT-DWC In Aromatics Industry

The following are the typical applications of GT-DWC in an aromatics complex:

  • Benzene / Toluene Column
  • Toluene / Xylene Column
  • Deheptanizer / Xylene Column
  • Debutanizer / Deisobutanizer Column
  • Stabilizer
  • Deheptanizer
  • Reformate Splitter

GT-DWC offers a 20-30% reduction in energy along with a 30% reduction in CAPEX for the above applications.


GTC Single Shell Absorption / Distillation Columns (GT-ADC)

GT-ADC combines two unit operations (absorption and distillation) in single shell. GT-ADC offers a significant advantage for columns using partial condensers. 

GTC-Single-Shell-Absorp-Distill-Cols

 
GT-ADC Operating Principle

  • Performs two unit operations (absorption and distillation) in a single column.
  • Lights are removed on the feed side of the dividing wall by reboiled absorption.
  • Top liquid product is separated from heavies on the other side of the dividing wall via distillation.

The benefits of GT-ADC are explained using a conventional TA stabilizer as an example.


Conventional Stabilizer Design 

  • Typically operates at higher pressure (8.5 kg/cm2g)
  • C5 / off gas spillover due to partial condensation. C5 product stream has higher vapor pressure. 
  • Higher bottoms temperature (233 C). Fired heater or HP steam required as heating medium.


GT-ADC Stabilizer
 

  • Lower operating pressure (2.7 kg/cm2g)
  • Clear separation between off gas and C5 product. C5 product has low vapor pressure and can be blended directly with gasoline.
  • Higher C5 recovery.
  • Lower bottoms temperature (188 °C). Lower temperature allows heat integration with other process streams.

Conventional-Stabilizer-Col-GT-ADC-Stabilizer

The following table provides a comparison between a conventional Stabilizer design vs. GT-ADC stabilizer. 

GT-DWS-Stabilizer-Table

In the event that improved product purity is not desired, GT-ADC will provide a 20-30% reduction in energy for the same product specifications as in the conventional design.